Liquid AI -Si alloys are usually given special treatments before they are cast to obtain finer or modified matrix and eutectic structures, leading to improved proper ties. For many years, sodium additions to hypoeutectic and eutectic AI -Si melts have been recognized as the most effective method of modifying the eutectic morphology, although most of the group IA or IIA elements have significant effects on the eutectic s tructure. Unfortunately, many of these approaches also have associated several founding difficulties, such as fading, forming dross in presence of certain alloying elements, reduced fluidity, etc. ln recent years, antimony additions to AI -Si castings have attracted considerable attention as an alternative method of refining the eutectic structure. Such additions eliminate many of the difficulties listed above and provide permanent (i.e. non -fading) refining ability. In this paper, the authors summarize work on antimony treatment of Al -Si based alloys.

Pouring of liquid aluminium is typically accompanied by disturbance of the free surface. During these disturbances, the free surface oxide

films can be entrained in the bulk of liquid, also pockets of air can be accidentally trapped in this oxide films. The resultant scattering of

porosity in castings seems nearly always to originate from the pockets of entrained air in oxide films. Latest version of ProCast software

allows to identify the amount of oxides formed at the free surface and where they are most likely to end-up in casts. During a filling

calculation, ProCast can calculate different indicators which allow to better quantify the filling pattern. The fluid front tracking indicator “

Free surface time exposure” has the units [cm2*s]. At each point of the free surface, the free surface area is multiplied by the time. This

value is cumulated with the value of the previous timestep. In addition, this value is transported with the free surface and with the fluid

flow.Experiments to validate this new functions were executed.